We have shown that suppression of Brk expression by RNA interference significantly decreases the secreted level of the matrix degrading enzyme MMP9 and the cytokine VEGFA, suggesting a role for Brk in regulating some of the processes involved in metastasis (proteolytic activity and neo-angiogenesis). As well as being able to modify the extracellular environment and to regulate angiogenic cytokine production, disseminating tumour cells must be able to survive in the circulation. We have also shown that Brk suppression increases the levels of cell death observed in breast carcinoma cells in suspension culture, implicating Brk in promoting anchorage-independent survival. In addition, suppression of Brk in suspension culture alters the relative levels of Bcl-x proteins in favour of Bcl-xS. As elevated Bcl-xL levels have been linked to chemotherapeutic resistance, targeting Brk may have benefits in overcoming chemoresistance in disseminating breast tumour cells.